Apparatus for treating ores and other materials.



H. B. How/mp. APPARATUS FOR TREATING ORES AND OTHER MATERI ALS.

' v APPUCATION FILED JUNE 17, I915. v1,164,1 9, Patented Dec. 14, 1915.

HENRY B. I IOVLAND, OF DULUTH, MINNESOTA.

APPAEATUS FOR TREATING ORES AND OTHER MATERIALS.

Specification of Letters Patent.

Patented Dec. 14,1915.

Application filed June 17, 1915. Serial No. 34.591.

To all whom itmag concern:

Be it knownthat I, HENRY B. HovLAND, a citizen of the United States,residing at Dulutlncounty of St. Louis, and State of Minnesota, haveinvented certain new and useful Improvements in Apparatus for Treating,Ores and other Materials; and I .do hereby declare the following to be afull, clear, and exact description of the invention, such as will enableothers skilled in the art to which it appertains to make and use thesame.

The present invention relates to apparatus for treating ores and othermaterials, and has for its object to provide an apparatus which iscommercially adapted for sulfating ore pulp, then sulfidizing the sameand subsequently floating off thesulfids in the manner hereinafterdescribed.

The present application is directed specifically to a commercial type ofapparatus, one form of which is disclosed in my copending application,Serial No. 31,898, filed June 3, 1915, in addition to a modified form ofthe apparatus. involving lhe same principles of operation, but designedespecially for laboratory use. In said application,

both forms of the apparatus are claimed broadly and the laboratoryapparatus is claimed specifically. In the present appli cation, thecommercial form of the apparatus is claimed specifically.

I have found in practice that in sulfating materials, if the reactingfluid constituents.

such as available sulfur and available oxygen under superatmosphericpressure, are brought into the presence of the material to be sulfated,the superatmospheric pressure greatly promotes the reaction. The resentapplication. contemplatesa commercial apparatus for permitting such aprocess to-be carried on continuously and on a relatively large scale.

The invention further contemplates a combination of ore treating unitsin Whichthe ore may be successively treated, so that the comminuted oreintroduced to the machine will be discharged from the last unit intheform of sulfids which are floated ed and the residual gangue'andliquor'which'are' drained'olf in the manner hereinafter described.

The invention is illustrated in the accompanying drawing, in whichFigure 1 is a vertical section, partly in eleration, of the apparatusillustrated more or less diagrai'nmatically; Fig. 2 is a transversevvertical section taken on the line 22 of Fig. 1; Fig. 3 is a brokenperspective view of a portion of the flotation unit; an'd Fig. 4 is ahorizontal section taken on the line 4+4: of Fig. 2.

In the form of the apparatus illustrated in the drawing, four main unitsare assempasses into the flotation unit denoted generally by thereference character E.

The sulfating unit B comprises an outer casing 1 capable of withstandingsuperatmospheric internal pressures, and preferably has a protectivelining of Wood or other suitable material, ind cated at 2. ofthe linmg 2which are spaced from the Certain parts outer casing 1 are provided withopenings 3 to equalize the pressure on both sides of the lining. I

Positioned within the casing 1 are a plurality of containers 4,throughwhich the ore pulp successively passes in its travel through thesulfating unit. The containers at may be constructed in any suitablemanner, but

preferably they are formed by positioning partitions 5 in an inclosedcasing 6. The ar-- titions 5 are provided at their lower portions withopenings 7 and at their upper portions with openings 8. It is,therefore, obvious that material under treatment may pass from onecontainer to the next through the lower openings and the gaseous; fluidsabove the surface of -the liquid inthe containers may pass from onecontainer to the next through the upper openings. It is also obviousthat before either the material can be discharged from the containers orthe gaseous fluids permitted to escape into the casingl, all of thecontainer must be traversed by the gaseous fluids and the material undertreatment. After the gaseous fluids 105 have so passed through all ofthe containers, theyare discharged, through the opening 9 lnto the outercasing 1 and then through the bleeder valve- 10. in the mannerhereinafter described.

Positioned in each of the containers +1 is a rotary agitator 11. As theagitator constitutes the subject-matter of. one of my copendingapplications, it is suflicient for the present purposes to know that theagitator heads are carried by hollow stems 12 and are capable ofdelivering through radial passages provided in their heads, gaseousfluid which is drawn down through the interior of the hollow stems 12.The. tops of thestems are closed, but openings 13 are provided in thestems just above the level of the material in the containers through.

vsha ft 16, which may be driven from a. pulley 17 through a knucklejoint 18. The pulley 17 is preferably positioned outside of the casing 1and the friction wheels 14, for driving the agitators.- are preferablypositioned just above the top of the casing 6.

The comminuted ore or other material to be treated is fed into thecontainers from either one of the ore locks A through the intermediaryof a pipe 19. In the present instance, two feed ore locks are shown, one

being indicated at 1 and the other at 2. w

The ore locks are provided with inlets con trolled by the gate valves 3and 4 respectively, and outlets controlled by the gate valves and (3,respectively. The comminuted ore may be fed to either of the lock binsfrom a bin '7" by means of the conveyer 8 A similar compound conveyer 9positioned below the outlets of the ore locks feeds the ore from eitherthe ore lock 1 or 2 into the pipe 19. The interior of the bins 1 and 2may be placed in communication with the interior of the casing l bymeans of the connecting pipes 10 and 11, respectively. These pipes arecontrolled'by means of the three-way valves 12 and 13 respectively, bymeans of which the interior of the.

bins 1 and 2 may be placed in communication with the atmosphere 'or elsein communication with the interior of the casing 1. I

ater is introduced into the apparatus preferably through a pipe 20controlled by valve 21 and communicating with the pipe 19, through whichthe dry ore passes. The

water introduced through the pipe 20 mixes with the dry ore and the orepulp passes into the end. container. 4. The fluid re acting constituentsabove referred t0, which may be a mixture of substances containingavailable sulfur and available oxygen, such as sulfurous acid and air orsmelter smoke, are admitted to the containers through a pipe 22controlled hv a valve The sulfate liquor passes from the bottom of thelast container 1 through a pipe section 24; and rises in. the pipe 25,while the sands drained from the last container pass downwardly in thepipe The sulfate liquor rises through the pipe 25v into areceptacle .26,and then overflows into apipe 27 leading downwardly toward the ore locksC. The receptacle 26, therefore serves to maintain a constantlevel ofthe liquid in the containers.

After sulfating, it may sometimes be desirable to add certain materials,such as ferric sulfate, to the sulfated substance to place the same inproper condition for sulfidizing in the unit D, hereinafter described.The ferric sulfate serves to neutralize the free sulfurous acid and alsoserves to react for sulfidizing purposes with the calcium sulfidsubsequently added in the'unit D. For this purpose, a bin 28-is providedhaving an inlet'controlled by a gate valve 29 and an out let controlledby a gate valve 30. Material may be conveyed from the bin 28 into thereceptacle 26 by means of a conveyer 31. A connecting pipe 32 places theinterior of the casing 1 in communication with the interior of the bin28 when the three-way valve is in one position, thus equalizing thepressure in the bin and casing, and places the interior of the bin 28 incommunication with the atmosphere when in another position.

Samples may be withdrawn from the sulfating unit for testing through apipe 34:v

passing downwardly into the last container and ending in the vicinity ofthe discharge pipe 24. This pipe may be provided with acontrolling valvewhich, when opened, will permit the pressure in the casing to force someof the material out into a suitable receptacle for testing.

The lower end of the pipe 25 communicates with a cross conduit 1 inwhich operates a conveyer 2 for conveying the sands into either thereceiving lock bin 3 or 4. A gate valve 5 controls communication betweenthe pipe 25 and the cross conduit 1 and may be left in such a positionthat the sands will pass into the cross conduit 1 only with sufficientrapidily to cause an accumulation of the sand in the lower part of thepipe 25, thereby causing the sulfate liquor to rise in 'the pipe 25 andoverflow into the pipe 27, as above described. The lower end of the pipe27, through which the sulfate liquor descends, is provided with twobranches 6 and 7 controlled by the gate Valves 8 and 9, respectively.The sulfate liquor passes through either the branch 6 and 7 dependingupon which gate valve 8 and 9 1s opened, and. then mixes with the "andthen the mixture is delivered to either the lock bin 301 l? dependingupon which gate valve 10 or 11 is open.

The pressure may be equalized in the casing 1 and the ore lock 3 bymeans of a connecting pipe 12 controlled by a valve 13. Likewise, thepressure in the ore lock 1 'may be equalized with the pressure in the-asing 1 by means ofthe connecting pipe 11 controlled by a valve 15. Abranch pipe 16 connects the pipe. 12 with the space under the bin floor22", thereby equalizing the pressure above and below the bin floor. Thisbranch pipelG iscontrolled by a three-way valve 1? which may serve toplace the pipe 12 in communication with the space below the binfioor2201 may serve to place the interior of the bin 3 in communication withthe atmosphere when 13 is closed; A branch pipe 18 and three-way valve1.) associated with the orelock or bin 1 serve the same purpose withrespect to the ore lock 1 as the branch pipe 16" and three-wav valve 1Tjust described.

The outlets of the ore locks 3 and 4: are controlled by the gate 'alves20 and 21. The material is fed from either the ore lock 8 or .1 into thesulfidizing unit D, which may comprise ,a tank or container 1 to whichthe sulfidizing agent may be admitted from a bin 2 by means of aconveyer 3. Passing downwardly intothe container-l is a hollow tube +1which terminates at a point just above the bottom of the container 1 Thematerial in the container 1 is drawn up through the pipe P by suctionproduced by means of the rotary element 5 comprising two spacedplateshaving radial passages 6 positioned therebetween. This rotaryelement may be driven by means of a pulley 7 connected therewith, andwhen so driven will draw material up through the pipe 4, and thendeliver the material radially in all directions in the container 1 Forthis purpose, the interior of the pipe P is in communication with thespace between the plates of the rotary element (3. Some of the sandspassing up- .wardly through the pipe 4 may tend to clog the same and inorder to prevent this,

a conveyer 8 is preferably positionedinside of the pipe 4 and is rotatedby means of a pulley 9. The outlet of the sulfidizing container 1 iscontrolled by means of a gate valve 10. \Vhen this valve is opened, thematerial then passes into the flotation unit E.

The flotation unit may comprise a plurality of containers 1 separated bymeans of vthe partitions 2 having openings 3 in their lower portion topermit passage of the material from one container to ill): next. Eachcontainer has positioned therein a tapering neck portion 4' above theopening in Whichis provided a rotary skimmer 5*. Each conof the materialin the containers.

tainer has positioned therein an agitator 11 similar to that used in thesulfating unit 13 and the rotary shimmers 5 may be secured directly tothe stems of the agitators. will be noted from r, the skimmers maycomprise a wheel-like structure having radial spokes (S for blowing offthe froth and for throwing the same oh by actual contact therewith. Thestems of the agitators pass upwardly through the partitions 7 and 8(Figs. 2 and 3) and the agitator stems are interconnected just above thelower partition 7 As best shown in Figs. 2 and 3, the upper portions ofthe series of containers are inclosed by means of a closure-likeportion.

of the casing con'iprising the top 9 and the sides 10. The top 9 restsupon the transverse supports 11 (Fig. 1) and the sides 10 are boltedagainst the partitions 2 by means of the bolts 12". As shown in Figs. 2and 3, there is an opening left at each side of the casing between thelower edges of the upper side walls 10 and the upper edges of the lowerside walls 13 These openings are ndicated at 11 and are for the purposeof permitting the froth skimmed from the tops of the containers to passinto the troughs 15, one of which is provided at each side of the casingand runs longitudinally thereof. It will be noted that the partitions 7and 8 are of less width than the top portion of the casing, and,therefore, instead of fiuidwlrich,

in the present instance, is air, being drawn down through openings inthe sides of the agitator stems, it is drawn down through the tops ofthe agitator-stems which are left As a open for the purpose. Lateralclosures 16 hinged to the upper portion of the casing, as

shov: at 17 serveto inclose the troughs 15 and confine the air, or anyother gaseous fluid which may be used, in the casing, so that theagitators will circulate the same air over and over again through thematerial in the containers.

The material is introduced to the flotation unit E from the sulfidizingunit D through a. conduit 17". In order to place the sulfids incondition for floating, it is necessary to add thereto a small quantityof oil or similarmaterial, and this may be introduced from a receptacle18 through a valved outlet 19? discharging into the conduit 17. Aspitzkasten 20*, disposed adjacent to the last container 1 and incommunication therewith at the lower portion of the last container,serves to maintain a constant level A valve 21 provided at the lowerportion of the spitzkasten permits the gangue and residual sands to bedrained therefrom, and the liquid part of the pulp overflows into and iscarried away by trough 22.

The operation of the appa atus as above described is as follows.-Assuming that all of the valves are closed, the ore or other materialto be treated is thoroughly crushed and ground to pass an SO-meshscreenand is fed from the bin 7" intoeither the ore lock 1 or 2. Assumingthatv the material is' fed first into the lock 1*, the gate valve 3associated therewith is opened and the conveyer 8 is rotated to feed thematerial into the lock bin 1. When the orelock has been filled, the gatevalve 3 is closed and the valves 10, 5and 13, controlling communicationbetween the sulfating unit and the ore =locl; 3, are opened andthree-Way valve 12 isso turned as to place the feed ore lock 1 incommunication wit-lithe. interior of. the casing 1 of the sulfatingunit. The valve 21 of the sulfating unit is then opened to admit waterthrough the pipe ,20 into the containers 4: until the proper level isreached, and thereafter the valve 21 is left open the proper amount tomaintain a constant level of the liquid in the containers during thesulfating operation. The valve 23 is then. opened to bring into thepresence of the. material in the containers, a mixture of sulfurous acidand air, or other reacting agent or agents, such as smelter fumes. TheSe fluid .constituents are admitted until the pressure in the casingreaches approximately 100 lbs. to'the square inch, andthereafter thepipe 22 is connected to a sou rce of sulturous acid and air supply undera constant pressure of about 100 lbs. to the square inch. Due to thepresence of the connecting pipesbetween the feed ore locks and thedischarge ore. locks, the same pressure obtains in all parts of theapparatus and therefore the passage of material from one part to theother takes place the same as if all the parts were positioned in onecasing capable of maintaining the same pressure on all the parts.

The gate valve 5 controlling the outlet from the ore lock 1% is thenopened and material is then gradually introduced by means of theconveyert) through the pipe 19 in the containers 4. This feeding of thematerial is readily accomplished, since the pressure in the orelock 1 isthe same as that in the containers. The agitators 11 are then set inoperation and thefluid reacting constituents in the containers are drawndown through the openings 13 and .the hollow stems of the agitators anddelivered to the material in the contamers by the agitator heads. Thesuction zone produced in the vicinity of each agitator headautomatically draws the fluid constituents down into the liquid andcirculates them through the liquid in the form of finely divi edbubbles.

The fluid is successively passed from one container to the next and ineach container is circulated through the material, so that by the timethe last container has been reached, a substantial amount of theavailable sulfur and available oxygen has been:.-.

used from the sulfurousacid and air. Fresh sulfur-ous acid and 8.11,however, are-com stantly supplied throughthe pipe 22 and the bleedervalve 10 maybe partially opened to permit a constant circulation-of thesulfurous acid and air through e containers, and

then into the casing through. the opening 9,

and thence through -the' bleeder valve 10. The sulfurous acid air aresupplied under constant premure and thevalve .10 is left open, orpartially open, determined by the amount ofreacting gaseous constituentsrequired by the material-under treatment. It is obvious that the fluidreacting constituents need not be admitted at the same end of theapparatus as the material, as it may container, it is sulfated and thesulfate liquor passes through the pipes 25 and 27 into the receivinglock bin 3, the valve 8 hav ing been previously opened for this purpose.

On its Way to the lock bin 3, however. the

sulfate liquor has been supplied With material from the bin 28 to placeit in proper condition for sulfidizing, it being understood that thevalve 33 is first so turned as to equalize the pressure in the bin 28and the casing 1, so as to permit feeding of material from the bin intothe receptacle'26, and that the valve 30 controlling the outlet of thebin is first opened. The-bin 28 maybe refilled by closing the gate valve30 and reducing the pressure in the bin through the three way Valve 33.

The gangue and sulfate liquor discharged from the sulfating unit passthrough the gate'valve 10 into the receiving ore lock 3 in which thepressure is the same as in the casing 1. The process is continued untilthe receiving ore lock 3 is filled, at which time, it will be assumedthat the material to be treated has been completely discharged from, theore lock 1. During the discharge .ofth

' material from the ore lock 1, however, the

ore lock 2 has been filled by reversing the direction ofro tation of theconveyer 8. The

process may," therefore, be continued by equalizing the pressure in .theore lock 2 and the casing 1 through the pipe 11, and then feedingmaterial from the ore lock 2 into the sulfating unit B. The pressure inthe ore lock 1 may then be reduced by turning the three-Way valve 12 toplace the in terior of the ore lock in communication with theatmosphere, before which, however, the gate valve 5 must be closed. Theore lock may then be refilled while the material is rior of the lock binin communication with the atmosphere, thereby reducing the pressure.After the gate valve 20 is opened, the material may be fed from the orelock 3 into the sulfidizing unit D. When the ore lock 4 is full, thepressure in this'ore lock may be reduced by means of the three-wayIv-a'lve 19 after valves 11 and 15 are closed,

and the material then fed from the ore lock 4 into the sulfidizing unit,during which time, the ore lock 3 may be refilled.

In the sulfidizi'ng unit, the material has mixed therewith thesulfidizing agent and is circulated through the pipe 1 and thrownoutwardly by means of the rotary element 6 to thoroughly mix thematerials and produce a better sulfidizing action. The sulfidizedmaterial is discharged through the gate valv'e 10 into the flotationunit in which. the air or other fluid circulated through the materialproduced numerous finely divided bubbles which rise through the pulp andcarry with them the oil-coated sulfidized' metal. This produces anaccumulation of froth at the top of each container whichis skimmed offby the skimmers 5 and thrown against the walls of the casing. The froththen drains off into the troughs 15 and may be conducted to any suitableplace. The liquid part of the pulp having been deprived of copper 'orother metal in the flotation unit, flows over the edge of thespitzkasten' into trough 22 and is drained off and the gangue maybewithdrawn from the bottom of the spitzkasren through the Valve 21. Itwill be over and over again in being drawn down through the agitatorsand delivered to the material. This is for the purpose ofrestricting thesupply of oxygen, for if. too much oxygen is supplied, the copper in theprecipitated copper sulfidhas a tendency to form copper sulfate.Therefore, the less oxygen contained in the air, thebetter, since themain purpose of circulating the fluid through the material in theflotation unit is to produce bubbles for carrying the sulfidized metalupwardly to the surface.

From the foregoing description, it will be seen that although thesulfiatingis carried out under superatmospheric pressure, the use of thesuperatmospheric presure does not hinder the feeding of the material tothe apparatus or discharge the material therefrom, due to thearrangement of the feeding and receiving ore looks. I do not wish to belimited, however,'to the number of feeding and receiving ore locksshown, 7 since it may be desirable to vary the number employed.

The sulfating and flotation units in combination produce in effect acontinuous series of containers through which the material successivelypasses, and in each of which an agitator is provided for maintaining aconstant circulation of the gaseous fluid in the container through thematerial, the fluid being confined in the group of containers so andcaused to pass through the material in all of the containers.

Obviously numerous modifications and changes may be made in the detailsof construction as above described, without departing from the spirit orscope of the invention, as defined in the accompanying claims.

' Vhat I claim is r- 1. An apparatus for treating ores'and othermaterials, comprising an inclosed casnoted that a, body of air isconfined in the flotation unit and is used ing adapted to inclose thematerial'to be treated, an inclosed bin, said casing and bin adapted towithstand super-atmospheric pressure, and means to permit passage ofsaid material from the bin'to the casing while both are underthe samesuperatmospheric pressure.

An apparatus for treating ores and other materials, comprising aninclosed casing adapted to inclose the material to be treated, aninclosed bin, said casing and bin adapted to withstand superatmosphericpressure, means to equalize the pressure in the bin and casing, andmeans to permit passage ofsaid material from the bin to the casing whileboth are under the same super-' atn'iospheric pressure.-

3. An apparatus for treating ores and other materials undersupcratmospheric pressure, comprising an inclosed casingfan inclosedfeed bin, and an inclosed receiving bin all connected by passagesserving to establish and maintain equal internal pressures in the binsand easing, means for advancing the material under treatment from thefeed bin to the casing, means for ad-' vancing the material from thecasing to the receiving bin, and means for supplying and .dischargingfluid agents to and from the apparatus. V

4. An apparatus for treating ores and other materials undersuperatmospheric pressure, comprising an inclosed. casing, a pluralityof inclosed feed bins, and a plu- -rality of inclosed receiving bins,all c'onnectedby passages serving to establish and maintainequal'internal pressure between the,- said casings and said bins, meansfor ad.- vancing material under treatment from the said feed bins to'thesaid casing, means for l30 advancing the material from the casing to thereceiving bins. and means for supplying and discharging lluid agents toand from the apparatus.

Apparatus for treating ores and other material, comprising a casingadapted to withstand 'superatmospheric internal pressures and adapted toinclose a body of the material to be treated, an inclosed bin fordischarging material into the interior of the v casing, means to admitfluid under superatmospheric' pressure to the casing, an inclosed binfor receiving material discharged from the casing, and means to equalizethe pressure in the casing and both of said bins. 6. Apparatus fortreating ores and other material, comprising an inclosed casing adaptedto withstand super-atmospheric internal pressures and to contain thematerial to be treated, a plurality of inclosed bins for receivingmaterialdischarged from the casing, means to discharge material from theeasing into any one of said bins, and means to equalize the pressure inany one of said bins with the pressure in the casing.

7. Apparatus for treating ores and other material, comprising a. casingadapted to a, Withstand superatmospheric internal pressures and adaptedto inclose a body of the naterial to be treated, a plurality of inclosedbins for discharging material into the interior'of the casing, means tofeed material from any one of said bins to the casing, a plurahty ofreceiving b1ns, means for feedmg material from thecasing into any one ofsaid receiving bins, and means to equalize the pressure inthe casing andin any one or more of said bins.

standing superatmospheric internal pressures, means for holding materialand iteeding it into the interior of-the casing,'n'ieans toreceivematerial discharged from the easing, and means to equalize thepressure in thecasing with that in'the receiving and fee'dmg means.

9. -Appar""tus"for treatingQores and other -withstand"superatmos hericinternal res- .sures and adaptedto nclose a body 0 the materials,comprisinga casing adapted to material to be treated, an inclosed binfor discharging material into the interior of the casing, said binhaving a valve-controlled ;inlet and a valve controlled outlet, andmeans for equalizing the pressiiiein thebin and casing.

'10. Apparatus for treating ores and other material, comprising a casingadapted to Withstand superatmospheric internal pressures and adapted toinclose a body of the material to be treated, a; pluraiity of in closedbins for feeding material. into the interror or the casing, each of saidbins having a itl l ll:l' llill inlet: and :1 ab P -m trolled outlet.means for 'l'eeding uni! i from any one oi said bins to the casing.means to equalize the pressure in the casing and in any one or more ofsaid bins.

11. Apparatus for treating ores and other material, comprising a casingadapted to withstand superatmospheric internal pressures and adapted toinclose a bodyot' the material to be treated, a pluralityot inclosedbins for feeding material into the interior of the casing, each of saidbins having a valve-controlled inlet and a valve-controlled out-let,means for feeding material from any one of said bins to the casing.means to equalize. the pressure in the casing andin any one or more ofsaid bins a plurality of inclosed receiving bins into which the materialmay be discharged from the casing, each of said receiving bins having avalve-controlled inlet and a valve-controlled outlet, and means toequalize the pressure in the'casing and any one or more of saidreceiving bins. I

12. Apparatus for treating ores and other material, comprising aplurality of containers, means to introduce the material to be treatedto the containers, means to permit passage of the material through thecontainers successively, a, rotary agitator in each of said containers,a casing inclosing said containers capable of withstanding relatively high. internal pressures,'and means to admit fluid-reacting constituentsunder superatmospheric pressure to the containers.

13. A paratus for treating ores and other materia s, comprising a casingadapted to Withstand superatmospheric internal pressures, a plurality ofcontainers positioned therein, means to admit the material'to be treatedto the containers, means to permit passage of the material through thecontainers successively, means to discharge the material from thecontainers after having 1 passed successively therethrough, means topass fluid-reacting constituents successively through the containers,and an agitatorpositioned in each container, ceapable of maintaining acirculation of the fluid-reacting constituents. through the material inthe container.

14.. A paratus for treating ores and other materia 5 comprising a.casing adapted to withstan superatmospheric internal pressures, aplurality of containers inclosed by said casing, means to cause thematerial to be treated "to successively pass through all of saidcontainers, means to cause fluid-reacting constituents undersuperatmospherlc pressure to-successivcly pass through all of saidcontainers, an agitator in each of said containers adapted to maintain acirculation of the fluid-reacting constituents in the container throughthe material therein, means to discharge the used reacting constituents16. Apparatus for treatingores and other materials, comprising a seriesof containers,

15 means for causing the material under treatment to pass successivelythrough all of said containers, means to confine a body of fluid abovethe level of material in the containers,.

and an agitator in each container capable of 20 maintaining acirculation of the, fluid through the interior of the agitator and thematerial in the container.

17. Apparatus for treating ores and other materials, comprising twoseries of contain- 25 ers, means for causing the material undertreatment to passsuccessively through all of said. containers, meansassociated with each series of containers for confining a body of'fluidabove the level of the material in 30 the containers, and an agitator ineach of said containers capable of maintaining a circulation of thefluid through the interior of the agitator and the material in the con-18. Apparatus for treating ores and other material, comprising an'inclosure adapted to Withstand superatmospheric internal pressures andto contain a body of the material to be treated, an inclosed binconnected with the casing, and means to equalize thepressure in thecasing with that in the bin.

19. Apparatus for treating ores and other material, comprising aninclos'ure adapted to Withstand superatmospheric internal pres i suresand to contain a body of the material to be treated, a plurality ofinclosed bins connected with the inclosure, and means to equalize thepressu e in the inclosure with the pressure in any one of said bins.-

' 20. Apparatus f or treating ores and other material, comprising aseries of containers, means for causing the material under treatment topass successively through said contain'ers, and an agitatorin eachcontainer adapted to maintain a circulation of gaseous fluid through theinterior of the agitator and the material in the container.

In testimony whereof I afiix my signature.

HENRY B. HOVLAND.

Copies of this patent may be obtained for five cents each, by addressingthe "Commissioner o l Patents, Washington, D. 0.

